Search Publications

Models and data analysis tools for the Solar Orbiter mission
DOI: 10.1051/0004-6361/201935305 Bibcode: 2020A&A...642A...2R

Fedorov, A.; Budnik, E.; Williams, D. +102 more

Context. The Solar Orbiter spacecraft will be equipped with a wide range of remote-sensing (RS) and in situ (IS) instruments to record novel and unprecedented measurements of the solar atmosphere and the inner heliosphere. To take full advantage of these new datasets, tools and techniques must be developed to ease multi-instrument and multi-spacec…

2020 Astronomy and Astrophysics
SOHO SolarOrbiter 75
Magnitude and direction of the local interstellar magnetic field inferred from Voyager 1 and 2 interstellar data and global heliospheric model
DOI: 10.1051/0004-6361/201937058 Bibcode: 2020A&A...633L..12I

Izmodenov, Vladislav V.; Alexashov, Dmitry B.

In this Letter, we provide constraints on the direction and magnitude of the pristine (i.e., unperturbed by the interaction with the Sun) local interstellar magnetic field. The constraints are based on analysis of the interstellar magnetic field components at the heliopause measured by magnetometer instruments on board Voyager 1 and 2 spacecraft. …

2020 Astronomy and Astrophysics
SOHO Ulysses 64
Thermal-nonthermal energy partition in solar flares derived from X-ray, EUV, and bolometric observations. Discussion of recent studies
DOI: 10.1051/0004-6361/202039529 Bibcode: 2020A&A...644A.172W

Mann, G.; Warmuth, A.

Context. In solar flares, energy is released impulsively and is partly converted into thermal energy of hot plasmas and kinetic energy of accelerated nonthermal particles. It is crucial to constrain the partition of these two energy components to understand energy release and transport as well as particle acceleration in solar flares. Despite nume…

2020 Astronomy and Astrophysics
SOHO 41
Evolution of the Alfvén Mach number associated with a coronal mass ejection shock
DOI: 10.1051/0004-6361/201936449 Bibcode: 2020A&A...633A..56M

Gallagher, Peter T.; Carley, Eoin P.; Maguire, Ciara A. +1 more

The Sun regularly produces large-scale eruptive events, such as coronal mass ejections (CMEs) that can drive shock waves through the solar corona. Such shocks can result in electron acceleration and subsequent radio emission in the form of a type II radio burst. However, the early-phase evolution of shock properties and its relationship to type II…

2020 Astronomy and Astrophysics
SOHO 31
Using radio triangulation to understand the origin of two subsequent type II radio bursts
DOI: 10.1051/0004-6361/201937273 Bibcode: 2020A&A...639A..56J

Jebaraj, I. C.; Magdalenić, J.; Kilpua, E. K. J. +7 more

Context. Eruptive events such as coronal mass ejections (CMEs) and flares accelerate particles and generate shock waves which can arrive at Earth and can disturb the magnetosphere. Understanding the association between CMEs and CME-driven shocks is therefore highly important for space weather studies.
Aims: We present a study of the CME/flare…

2020 Astronomy and Astrophysics
SOHO 28
Asymmetric expansion of coronal mass ejections in the low corona
DOI: 10.1051/0004-6361/201936664 Bibcode: 2020A&A...635A.100C

Cremades, H.; Iglesias, F. A.; Merenda, L. A.


Aims: Understanding how magnetic fields are structured within coronal mass ejections (CMEs), and how they evolve from the low corona into the heliosphere, is a major challenge for space weather forecasting and for solar physics. The study of CME morphology is a particularly auspicious approach to this problem, given that it holds a close rela…

2020 Astronomy and Astrophysics
SOHO 23
Power spectra of solar brightness variations at various inclinations
DOI: 10.1051/0004-6361/202037588 Bibcode: 2020A&A...636A..43N

Solanki, S. K.; Shapiro, A. I.; Tagirov, R. V. +4 more

Context. Magnetic features on the surfaces of cool stars lead to variations in their brightness. Such variations on the surface of the Sun have been studied extensively. Recent planet-hunting space telescopes have made it possible to measure brightness variations in hundred thousands of other stars. The new data may undermine the validity of setti…

2020 Astronomy and Astrophysics
SOHO 23
Longitudinal filament oscillations enhanced by two C-class flares
DOI: 10.1051/0004-6361/201937291 Bibcode: 2020A&A...635A.132Z

Guo, J. H.; Zhang, Q. M.; Xu, A. A. +1 more

Context. Large-amplitude, longitudinal filament oscillations triggered by solar flares have been well established in the literature. However, filament oscillations enhanced by flares have never been reported.
Aims: In this paper we report the multiwavelength observations of a very long filament in active region (AR) 11112 on 2010 October 18. …

2020 Astronomy and Astrophysics
SOHO 20
A statistical study of plasmoids associated with a post-CME current sheet
DOI: 10.1051/0004-6361/202039000 Bibcode: 2020A&A...644A.158P

Pant, Vaibhav; Banerjee, Dipankar; Patel, Ritesh +1 more

Context. Coronal mass ejections (CMEs) are often observed to be accompanied by flare, current sheets, and plasmoids/plasma blobs. 2D and 3D numerical simulations and observations reported plasmoids moving upward as well as downward along the current sheet.
Aims: We aim to investigate the properties of plasmoids observed in the current sheet f…

2020 Astronomy and Astrophysics
SOHO 20
When do solar erupting hot magnetic flux ropes form?
DOI: 10.1051/0004-6361/202038832 Bibcode: 2020A&A...642A.109N

Cheng, X.; Zhang, J.; Patsourakos, S. +2 more


Aims: We investigate the formation times of eruptive magnetic flux ropes relative to the onset of solar eruptions, which is important for constraining models of coronal mass ejection (CME) initiation.
Methods: We inspected uninterrupted sequences of 131 Å images that spanned more than eight hours and were obtained by the Atmospheric Imag…

2020 Astronomy and Astrophysics
SOHO 18